摘　　要

分布式發(fā)電(Distributed Generation)并不是一種全新的發(fā)電技術(shù)，在電能取代水力、蒸汽、燃煤成為能量驅(qū)動負載以前，絕大多數(shù)電能都是分布在需要能源的設(shè)備附近。隨著生產(chǎn)方式的集中發(fā)電、輸送方式的遠距離輸電與分配方式的大電網(wǎng)互聯(lián)的電力系統(tǒng)成為當今世界上百分之九十的電力供應(yīng)，其暴露的問題也在不斷增加，分布式電源與大電網(wǎng)并聯(lián)運行需求成為21世紀電力工業(yè)的發(fā)展方向，但含分布式電源的配電網(wǎng)的保護要與以往的保護有很大的差別，本文針對分布式電源并網(wǎng)后對主網(wǎng)保護的影響而設(shè)計一種微機型后備保護裝置。
論文首先分析了分布式電源的并網(wǎng)對傳統(tǒng)電網(wǎng)的繼電保護的影響，建立了分布式電源的并網(wǎng)模型，通過對并網(wǎng)模型的分析及繼電保護的相關(guān)知識，選取分布式電源并網(wǎng)保護的功能及整定值的設(shè)定，設(shè)計提出了一種基于ARM的嵌入式微機型的分布式電源監(jiān)控保護裝置。
接下來簡要介紹了一下分布式電源監(jiān)控保護裝置的硬件平臺，在基于LPC2468的最小系統(tǒng)上設(shè)計交流采樣電路、開關(guān)量輸入輸出電路、頻率測量電路。
論文的重點在于各種電網(wǎng)電氣量的計算方法，保護算法的目的是從離散的采樣值中計算出有用的信號，為保護邏輯判決提供準確而實時的依據(jù)。保護算法有很多種，本文提出的分布式電源保護裝置的算法有：基于同期并網(wǎng)的相位檢測算法，基于突變量的元件啟動算法，電流電壓序分量的計算方法，各種諧波分量的檢測算法及基本電氣量的檢測算法。所有算法所設(shè)定的信號模型都不一樣，大致可以分為正弦信號模型、周期信號模型與隨機信號模型，從時間窗、精度、計算量及速度等方面對每種算法的優(yōu)劣性作了分析。
最后把嵌入式操作系統(tǒng)uC/OS-II成功移植到LPC2468硬件平臺上，建立了多任務(wù)設(shè)計環(huán)境，保護裝置的每個功能都被分配到一個任務(wù)，且各任務(wù)都有不同的優(yōu)先級，定時采樣中斷任務(wù)、保護算法任務(wù)及故障處理任務(wù)是其中最主要的部分，各個任務(wù)相互協(xié)調(diào)完成了從并網(wǎng)投入、檢測監(jiān)控、保護切除的一系列工作。
分布式電源監(jiān)控保護裝置是繼電保護領(lǐng)域一個全新的課題，其主要功能還是在于檢測并網(wǎng)點兩側(cè)的信號來設(shè)定后備保護，用以輔助分布式電源內(nèi)部保護及主網(wǎng)保護設(shè)備，隨著分布式電源的大范圍并網(wǎng)，其應(yīng)用空間無限寬廣。

關(guān)鍵字　分布式電源；保護參數(shù)；保護算法；uC/OS-II；多任務(wù)設(shè)計



Abstract

Distributed Generation (DG) is not a new power generation technology, before the electricity as energy to drive the load replace the water, steam, coal-fired energy , the vast majority of electricity is distributed in the near the equipment which needed energy. As the power system which with the concentration of power production, long-distance of power transmission and large grid interconnection of power distribution mode to be the 90 percent of the electricity supply in the world. The problems are also growing. With large distributed power grid parallel operation to become the development direction of the electric power industry in 21st century. However, distributed power protection is different from traditional relay protection. This paper focuses on the main impact of power protection after the distributed power grid to design a microprocessor-based back-up protection device.
Paper first analyzes the grid of distributed power to influence of the traditional grid relay protection, establish the distributed power grid model, and through analysis the grid model and the relevant knowledge of relay, design the distributed power gird protection function and setting the value of protection. Based ARM embedded to design a microprocessor-based distributed power monitoring and protection devices.
Then a brief introduction about the protection of distributed power protection hardware design, based on the minimum system of LPC2468 to design the AC sampling circuit, switch input and output circuits, frequency measurement circuit.
Paper focuses on various methods of calculating the amount of electrical power, the purpose of protect the algorithm is to calculate the useful signal from the discrete sample values, provide accurate and real-time data to the logical decision for the protection. There are many protection algorithms, the proposed algorithm for distributed power protection devices are: the phase detection algorithm based on the synchronizing grid, the components starting algorithm based on mutation, the calculation method of the current and voltage sequence component, the detection algorithms of harmonic components and the detection algorithm of basic electrical quantities. All the algorithms are not based the same signal model that can be divided into sinusoidal signal model, random periodic signal model and signal model. In terms of the time window, accuracy, speed and computation to analyze advantages and disadvantages of each algorithm.
Finally, embedded operating system uC/OS-II successfully transplanted to the LPC2468 hardware platform, then based on which to establish a multi-task design, each functional unit is assigned to a task, time sampling interrupt task, the protection algorithm task and the fault processing task are the most important part, and all the tasks coordinate to finish a series of works that grid connection, inspection and monitoring, fault cleaning.
Distributed power monitoring and protection device is a new subject area, its main function lies on signal detected of the both sides and to design the b..